Mutation studies in ascidians: A review

Abstract

Historically, mutations have had a significant impact on the study of developmental processes and phenotypic evolution. Lesions in DNA are created by artificial methods or detected by natural genetic variation. Random mutations are then ascribed to genetic change by direct sequencing or positional cloning. Tunicate species of the ascidian genus Ciona represent nearly fully realized model systems in which gene function can be investigated in depth. Additionally, tunicates are valuable organisms for the study of naturally occurring mutations due to the capability to exploit genetic variation down to the molecular level. Here, we summarize the available information about how mutations are studied in ascidians with examples of insights that have resulted from these applications. We also describe notions and methodologies that might be useful for the implementation of easy and tight procedures for mutations studies in Ciona.

The Cis-Regulatory Code for Kelch-like 21/30 Specific Expression in Ciona robusta Sensory Organs

“…Later, during neural tube closure, PCPs divide twice and give rise to a total of 8 cells at early tailbud stage, which express melanogenic genes belonging to the Tyrosinase (Tyr) family ( Tief et al, 1996 ; Caracciolo et al, 1997 ; Esposito et al, 2012 ; Haupaix et al, 2014 ; Racioppi et al, 2014 , 2017 ). The loss of Tyr function in Ciona results in pigment-free larvae ( Sordino et al, 2008 ; Crocetta et al, 2015 ), whereas some tunicate species (e.g., Molgula occulta ) have lost Tyr family genes and lack melanin pigmentation altogether ( Racioppi et al, 2017 ).…”